Note 7 - Earnings Per Common Share (Detail) - Reconciliation of Basic and Fully Diluted Earning Per Common Share (USD $)	3 Months Ended		6 Months Ended
	Jun. 24, 2012	Jun. 26, 2011	Jun. 24, 2012	Jun. 26, 2011
Net earnings	$ 11,662,000	$ 10,673,000	$ 29,907,000	$ 25,534,000
Earnings per common share	11,662,000	10,673,000	29,907,000	25,534,000
Earnings per common share (in Shares)	18,574,924	18,330,333	18,565,131	18,318,342
Earnings per common share (in Dollars per share)	$ 0.63	$ 0.58	$ 1.61	$ 1.39
Earnings per common share – assuming dilution (in Shares)	18,660,000	18,401,000	18,650,000	18,389,000
Earnings per common share – assuming dilution (in Dollars per share)	$ 0.62	$ 0.58	$ 1.60	$ 1.39
Stock Options [Member]
Effect of dilutive securities	85,542	71,144	84,696	70,822
Earnings per common share – assuming dilution	$ 11,662,000	$ 10,673,000	$ 29,907,000	$ 25,534,000
Earnings per common share – assuming dilution (in Shares)	18,660,466	18,401,477	18,649,827	18,389,164
Earnings per common share – assuming dilution (in Dollars per share)	$ 0.62	$ 0.58	$ 1.60	$ 1.39